DESCRIPTION: The primary goal of the proposed research is to develop a multiplexed serological test for blood banks that will enable simplification of pathogen testing, a unified typ of data for all tests, reduced training for technicians, and modular addition of new tests when needed. There are 14.6 million blood transfusions per year, and 9.5 million blood donors. Blood is tested for 6 unique pathogens routinely, others are tested on a seasonal basis or during pandemics, but tests for (for example) babesiosis and Chikungunya, are notably absent from routine screening, though their prevalence is of concern. Currently, adding tests for newly discovered pathogens can be arduous. We propose to validate 'immunosignaturing', a multiplexed serological diagnostic, for use in blood screening. Immunosignatures are highly data dense because they use hundreds of thousands of ligands simultaneously. The inherent specificity is very high, enabling a single test to distinguish multiple diseases, and the sensitivty enables pooling samples with equal or greater sensitivity than standard EIA or ELISA tests. Our in-situ lithography synthesis system enables high throughput production of assays that scales in cost as the number of assays increases. The technology can be applied to other diseases outside blood screening. The concept is to present the technology and a given single disease to the FDA for approval of the platform, then clinical validations using historical samples for each new disease test is presented to the FDA as needed. A formal proposal using a two-disease case study has already received positive FDA comments in 2014. This project has wide-reaching implications beyond blood testing, and the data generated has value outside the proposed research, and will be made public.